Samsung:Esc or F2 or F12. Users of ultrabooks from Samsung should disable the fast boot option in BIOS/UEFI before they boot from a USB device. To disable the fast boot, go to To access BIOS/UEFI > Samsung and find the combination of keys you need to press to access this.

VAIO:Esc, F10 or F11. On some Sony VAIO computers models you may need to press the Assist button.

Toshiba:F12

To access BIOS/UEFI

To access the BIOS/UEFI, find your PC manufacturer below to see what combinations of key you need: